- T7 RNA polymerase
T7 Polymerase is an
RNA polymerasethat catalyzes the formation of RNAin the 5'→ 3' direction. T7 polymerase is extremely promoter-specific and only transcribes bacteriophageT7 DNA or DNA cloned downstream of a T7 promoter. The T7 polymerase also requires a DNA template and Mg2+ ion as cofactor for the synthesis of RNA. The enzyme is strongly stimulated by BSA or spermidine. In contrast to bacterial RNA polymerases, T7 polymerase is not inhibited by the antibiotic rifampicin. The source of the enzyme is the T7 bacteriophage, which is a virus that infects only bacteria. This phage's polymerase has a very low error rate. T7 polymerase has a molecular weight of 99 kDa.
T7 RNA polymerase is commonly used to transcribe DNA which has been cloned into vectors which have two phage promoters in opposite orientation. RNA can be selectively synthesized from either strand of the insert DNA with different polymerases.
Homogeneously labeled single-stranded RNA can be generated with this system. Transcripts can be non-radioactively labeled to high specific activity with certain labeled nucleotides.
* Sastry SS, Ross BM. "Nuclease activity of T7 RNA polymerase and the heterogeneity of transcription elongation complexes." J Biol Chem 272 (1997 Mar 28): 8644-52.
* [http://academic.brooklyn.cuny.edu/chem/zhuang/Nicolas/enzymolo.htm T7 RNA Polymerase Enzymology]
Wikimedia Foundation. 2010.
Look at other dictionaries:
RNA polymerase II — (also called RNAP II and Pol II) is an enzyme found in eukaryotic cells. It catalyzes the transcription of DNA to synthesize precursors of mRNA and most snRNA and microRNA. [cite journal | author = Kronberg, R.D. | title = Eukaryotic… … Wikipedia
RNA-Polymerase — Enzymklassifikationen EC, Kategorie … Deutsch Wikipedia
RNA polymerase III — (also called Pol III) transcribes DNA to synthesize ribosomal 5S rRNA, tRNA and other small RNAs. The genes transcribed by RNA Pol III fall in the category of housekeeping genes whose expression is required in all cell types and most… … Wikipedia
RNA-dependent RNA polymerase — (RDRP), or RNA replicase, is an enzyme that catalyzes the replication of RNA from an RNA template. This is in contrast to a typical RNA polymerase, which catalyzes the transcription of RNA from a DNA template.Viral RDRPs were discovered in the… … Wikipedia
RNA polymerase II holoenzyme — is a form of eukaryotic RNA polymerase II that is recruited to the promoters of protein coding genes in living cells. It consists of RNA polymerase II (a subset of general transcription factors) and regulatory proteins known as SRB… … Wikipedia
RNA-dependent RNA polymerase — RNA dependent RNA polymerase. См. РНК репликаза. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
RNA polymerase — n. any of various polymerases that help form RNA from DNA or RNA … English World dictionary
RNA-Polymerase — RNA Polymerase, DNA abhängiges Enzym, das bei der ⇒ Transkription mRNA synthetisiert. Die R. entwindet den DNA Doppelstrang, lagert in 5 →3 Richtung komplementäre Nucleotide an den codogenen DNA Einzelstrang an und verbindet sie zu einem RNA… … Deutsch wörterbuch der biologie
RNA polymerase — RNA polymerase. См. РНК синтетаза. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
RNA polymerase — RNAP from T. aquaticus pictured during elongation. Portions of the enzyme were made transparent so as to make the path of RNA and DNA more clear. The magnesium ion (yellow) is located at the enzyme active site. RNA polymerase (RNAP or RNApol) is… … Wikipedia
RNA polymerase II subunit B4 — DNA directed RNA polymerase II polypeptide D (or subunit B4), also known as POLR2D, is a human gene. PBB Summary section title = summary text = This gene encodes the fourth largest subunit of RNA polymerase II, the polymerase responsible for… … Wikipedia